ANAHEIM, Calif. (AP) — Police and advocates are warning homeless people in Orange County to be careful if they sleep on the streets because a serial killer who is hunting the homeless has already killed three men.

Orange County Rescue Mission President Jim Palmer says his group is handing out flashlights and whistles to the homeless, in an effort to help them protect themselves.

Homeless people also are being encouraged to sleep in shelters or in groups.

The body of the first victim, 53-year-old James McGillivray, was found Dec. 21 near a Placentia shopping mall. The second victim, 42-year-old Lloyd Middaugh, was found on a riverbed trail in Anaheim a week later.

The third victim, 57-year-old Paulus Cornelius Smit, was discovered with fatal stab wounds outside a Yorba Linda library, where a photo of him stood at a small candlelit memorial this week.